Harry's use of an Unforgivable excused? (was: Who taught Voldemort?)

[Rebecca Dreiling]

No: HPFGUIDX 130591

Quick silver wrote:
Harry has no experience but he manages to shut Bella up
pretty quick. Imagine if he had practiced on spiders for a month
before hand.


You know I'm sure this has come up in discusssion before but Harry did use 
an Unforgivable curse in OoP.  Is he excused because of the context of the 
spell's use?  Is he excused because he was fighting LV?  Does anyone think 
that he will have to deal with a punishment for this in HBP?  Or is it that 
the war has started and all rules/bets are off as far as spells/curses are 
concerned?

Just curious if there is a thread discussing this.

Rebecca